Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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-Topic 326
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Finance Receivables and Loans, Net - Schedule of Financing Receivables, Nonaccrual Status (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2025	Mar. 31, 2024	Dec. 31, 2024	Dec. 31, 2023
Receivables [Abstract]
Financing receivable, nonaccrual, interest income	$ 4	$ 5
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing receivable, recorded investment, nonaccrual status	1,417		$ 1,486	$ 1,394
Financing receivable, nonaccrual, with no allowance	502		518
Consumer
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing receivable, recorded investment, nonaccrual status	1,223		1,375	1,275
Financing receivable, nonaccrual, with no allowance	487		512
Consumer \| Automotive
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing receivable, recorded investment, nonaccrual status	1,167		1,231	1,129
Financing receivable, nonaccrual, with no allowance	449		476
Consumer \| Consumer mortgage finance receivables
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing receivable, recorded investment, nonaccrual status	56		54	54
Financing receivable, nonaccrual, with no allowance	38		36
Consumer \| Other
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing receivable, recorded investment, nonaccrual status	0		90	92
Financing receivable, nonaccrual, with no allowance	0		0
Commercial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing receivable, recorded investment, nonaccrual status	194		111	119
Financing receivable, nonaccrual, with no allowance	15		6
Commercial \| Automotive
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing receivable, recorded investment, nonaccrual status	79		15	18
Financing receivable, nonaccrual, with no allowance	3		0
Commercial \| Consumer mortgage finance receivables
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing receivable, recorded investment, nonaccrual status	21		2	3
Financing receivable, nonaccrual, with no allowance	9		2
Commercial \| Other
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing receivable, recorded investment, nonaccrual status	94		94	$ 98
Financing receivable, nonaccrual, with no allowance	$ 3		$ 4